I forgot to return the book to you yesterday. So I（）today.A、might do it B、must do itC、had to do itD、must have to do it

-- I'd like to book a flight to Beijing, please.

-- _____.

A. No, you can't

B. Yes, sir, single or return?

C. We are busy.

D. Wait

A.Must; needn’t

B.Can; can’t

C.May; mustn’t

D.Can; mustn’t

下面程序的结果【 】。

include＜iostream.h＞

int f(int)；

void main() {

int x=1, i;

for (i=0; i＜3; i++)

cout＜＜f(x)＜＜‘ ’ ;

cout＜＜end1;

}

int f(int x){

int y=1;

static int z=3

y++;

z++;

return (x+y+z);

}

下列程序的输出结果是______。

include＜iostream.h＞

class base

{

int x,y;

public:

base(int i,int j){x=i;y=j;}

virtual int add( ){return x+y;}

};

class three:public base

{

int z;

public:

three(int i,int j,int k):base(i,j){z=k;)

int add( ){return(base::add( )+z);}

};

void main( )

{

three*q=new three(10,20,30);

cout＜＜q-＞add( )＜＜endl;

}

下列程序编译错误，因为add函数返回值是一个引用，故对return后返回值的要求是【 】。

include＜iostream. h＞

int& add(int x, int y)

{

return x+y;

}

void main( )

int i=3,j=19;

cout＜＜(add(i,j)+ =20)＜＜end1;

}

It was not long _______ I forgot it all.

A、then

B、when

C、after

D、before

以下函数的功能是：求x的y次方，请填空。double fun(double x,int y){ int i; double z; for(i=1,z=x;i<y;i++) z=z*; return z;}

有如下程序：

include＜iostream＞

using namespace std；

int fun1(int x) {return++x;}

int fun2(int &x) {return++x;}

int main(){

int x=1，y=2；

y=fun 1(fun2(x))；

cout＜＜X＜＜','＜＜y；

return 0：

}

程序的输出结果是______。